Hello. As per the title I have a few questions regarding drive offset and its affect with ‘last sector’ handling during CD ripping.

Some years back I ripped my CD collection using EAC to single image (album) FLAC with cuesheet. Not sure why but a week or so back I decide to have a look at CueRipper and grabbed a random CD (Pink Floyd – The Final Cut). I actually hit an issue with CueRipper with it raising an exception during gap detection (as per another thread) but that’s not the reason for the post.

What I discovered was that the MD5 within the FLAC was different to my earlier ripped master. My initial reaction was along the lines of what the...

As it happens I have 2 notebooks and 2 PC. The PC that was used for the ripping was retired but I managed to resurrect it and repeat the rip and it got the same MD5 as what was in the original (so the same system got the same MD5).

I then tried all others systems and found a relationship between the offset. Somewhat by chance, two systems have an identical offset of +102 and two have an identical offset of +667. Each system with the same offset results in the same MD5. In all cases, AccurateRip results (both AR1 and AR2) following ripping are fine.

Next step was to compare WAV files so I decoded each of the FLAC and compared within EAC. Both files are bit identical right up to what I would call last sector with the variation occurring in last 0.013’ of the WAV file (so last 1/75).

Upon reflection I expect this is probably quite normal and I note that AccurateRip does not use last 5 sectors (2940 samples) for its calculation. I presume this is intentional due to drive variation and the like.

I guess the question is should I be concerned about this or is this a case of OCD getting the better? Is there any ripping means that overcomes the variation of offset and drive capability that will result in bit identical WAV? Keep in mind I’m asking about the very last samples; I expect everything up to then to be bit identical which is the purpose of the offset value used with ripping.

It does seem to me that consistency will only be achieved where the drive has an absolute offset of less than or equal to 588. Any offset larger than that will result in a variation subject to EAC settings, offset value and drive capability when ripping the last samples.

Just out of curiosity, the FLAC MD5 for the album as above comes out as per below. I’d be interested in the value that others have for comparison as it will confirm my thinking to the cause and maybe as to which is the ‘better’ image copy. Thoughts?

LOL. Well I do have egg on my face and humbly admit to being very wrong for using LBA in that post (and any others if they exist).

You do now understand that drives that cannot overread which have offset corrections of +6, +12 and +102 will give different results when ripping the last track of a disc that contains PCM data which is non-null up to the very end, correct?

BTW, thanks for considering me an authority on the subject.

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Breath is found in waveform and spectral plots;DR figures too, of course.